[d2idan]

i bought it : 3COM 3CRWER100-75

i connected it to my pc and my SB4200 MODEM correct.

and then i configured it right on the wizard (if you have 3com router so it http://192.168.1.1 as you already know )

and now i cant surf on web. (now i can talk with you because i'm writing from a friend)

so in the wizard there when i go to status and logs and then i see
Default Gateway : NO IP ---- DISCONNECTED

and i should see an ip and CONNECTED.

and i dont have firewall

here's what i see when i do IPCONFIG /ALL :

and when i configured it in the wizard.. look at the picture
the default gateway adrees .. nothing

 

[djaburg]

Reset your cable modem by unplugging the power and then plugging it back in. I alway unplug the router too. I power on the cable modem and let it finish its boot process then I turn on my router and wait a minute or two and that usually does it. Normally the IP address that's assigned to the router is assigned based on the MAC address of the device. Right below where you have circled on your drawing you'll see the WAN MAC Address. Resetting the cable modem will release the IP address and then the next device that tries to get one, which in this case would be your router, should get a valid IP address.